Hypergeometric mean and variance
[MN,V] = hygestat(M,K,N)
[MN,V] = hygestat(M,K,N) returns the mean of and variance for the hypergeometric distribution with corresponding size of the population, M, number of items with the desired characteristic in the population, K, and number of samples drawn, N. Vector or matrix inputs for M, K, and N must have the same size, which is also the size of MN and V. A scalar input for M, K, or N is expanded to a constant matrix with the same dimensions as the other inputs.
The mean of the hypergeometric distribution with parameters M, K, and N is NK/M, and the variance is NK(M-K)(M-N)/[M^2(M-1)].
The hypergeometric distribution approaches the binomial distribution, where p = K/M, as M goes to infinity.
[m,v] = hygestat(10.^(1:4),10.^(0:3),9) m = 0.9000 0.9000 0.9000 0.9000 v = 0.0900 0.7445 0.8035 0.8094 [m,v] = binostat(9,0.1) m = 0.9000 v = 0.8100